Endocrine Abstracts

Background: Acromegaly is a rare neuroendocrine disorder caused by secretion of excessive levels of growth hormone. Somatostatin receptor ligands (SRLs) are first-line medical therapies for patients in whom surgery has failed or is contraindicated. We report a case who had inadequate response to multiple therapies including surgery,radiotherapy,octreotide,lanreotide,cabergoline and pegvisomant.

Case: An 44-year-old woman was admitted to our hospital with a past medical history of acromegaly diagnosed 6 months ago. Initially she was treated with transcranial surgery for a 3 cm hypophyseal macroadenoma. She was given steroid and L-thyroxin replacement therapy after surgery. Physical examination revealed an overweight female patient with enlarged nose,lips,coarse facial features, macroglossia and enlargement of both hands. She had been receiving lanreotide for 6 months. Serum growth hormone (GH) and IGF1 levels were 6.66 ng/ml and 1291 ng/ml respectively. MRI(Magnetic Resonance Imaging) showed a 1.5 cm and a 1.2 cm residual tumors with suprasellar extension and optic nerve traction. Bitemporal hemianopsia was present on visual field examination. Serum GH and IGF1 levels were 40 ng/ml and 3985 ng/ml preoperatively. In the course of the disease,persistent elevated GH and IGF1 levels were observed. Tumour debulking is not recommended because of the cavernous sinus involvement. Two years after surgery, 180 gy conventional radiotherapy was performed because of inadequate response to medical therapy. In the course of the disease medication was modified as follows: Lanreotide switched to octreotide, combined with cabergoline. 2 years later, pegvisomant was started at initial dosage of 10 mg/day then titrated. During this medication, eventhough a slight decrease was observed, IGF1 levels were stil high. Despite these regimens, the biochemical markers were stil elevated,visual field defects were stil present and MRI revealed no significant change in residues. 1.5 years later, all medications were stopped and pasireotide was started with dosage of 0.6 mg/s.c./daily. Within 3 months after pasireotide treatment, a significant decrease was observed on GH an IGF1 levels. At the end of 6 years,biochemical remission was achieved. For diabetes management she used insulin but after biochemical control, insulin was stopped and GLP-1 receptor agonists were given. Her blood glucose levels were normal with this medication.

Conclusion: Pasireotide is a multireceptor-targeted SRLs. It seems to be a proper medical option for treatment of severe acromegaly cases who are resistant to other SRLs.